When dispensing certain types of concentrated liquids, such as concentrated mouthrinses, from containers it is critically important that one be able to get the correct amount and concentration of active, flavor and other ingredients with each diluted dose. For example, some concentrated antimicrobial mouthrinse formulations require proper dilution to provide positive therapeutic plaque and gingivitis prevention benefits. Proper dilution requires the ability to accurately measure both the concentrated mouthrinse from the container, typically a bottle, and the dilution water from the tap or other water source.
For concentrated mouthrinses which are intended to provide therapeutic effects, such as prevention of plaque or gingivitis, patient compliance, i.e., the use of proper regimen, dosage and concentration, is also essential to the efficacy of the mouthrinse.
It is well known that patient compliance is adversely affected by increased difficulty in using a mouthrinse, particularly a concentrated one, which must be diluted each time it is used. Also, the ongoing quality and efficacy of a concentrated mouthrinse requires that it remain substantially free from contamination from germs and saliva from the mouths of users, or contamination from germs and foreign material from the air surrounding the package both before and after the package has been placed in service by the user.
In addition, some concentrated antimicrobial mouthrinse formulations work on the principle that when water is added, a stable organic and water solution transforms into a dispersion of tiny oil droplets within an aqueous phase. This is supposed to occur just prior to use. If water is introduced unintentionally into the concentrated mouthrinse in the bottle prior to use, the shelf stable, homogenous concentrated mouthrinse remaining in the container can be transformed into a mixture which will be unstable, ineffective and unappealing to the user before the next use cycle.
One prior art dispensing system for concentrated mouthrinses, most widely used in Germany, comprises a bottle, with or without a reducing orifice at its point of liquid discharge, that does not employ a closure which can serve as a dilution and use vessel. This design leaves it up to the consumer to use a separate cup or glass, and to either estimate by experience or to use an external measuring device to get the correct amounts of concentrated mouthrinse and dilution water based upon written instructions provided on the package. This approach is ambiguous to consumers, and they often do not get the recommended dose/concentration of diluted mouthrinse. It can also prove awkward in travel situations, since it requires the consumer to have a cup or glass of their own, and such a utensil may not be readily available.
A second approach, which has been practiced in the U.S., employs a flip-up cap on a bottle, with a snap-on dose cup that attaches to the bottle over the top of the flip-up cap. The dose cup has a concentrate line and a water line on it. This particular prior art design has three major drawbacks: 1) it is very difficult to get the correct amount of concentrate because the cup exhibits a relatively large cross-section along its entire vertical axis (this is necessary in order for it to fit over the flip-up cap) resulting in the concentrate fill line being very near the bottom of the cup and consequently very hard to visually sight through; 2) the dose cup is easily lost by the consumer, leaving the consumer without a way to accurately measure the correct concentrate dose or the proper volume of dilution liquid; and 3) the consumer must open the flip-up cap after the dose cup is removed, which represents an extra step which is made more difficult when the dose cup is in one hand and the bottle is in the other. In addition to the foregoing drawbacks, the flip-up cap also requires the consumer to place his or her fingers on or near the product discharge orifice in the flip-up cap in order to initiate the concentrate dispensing process. This could, of course, be unsanitary.
Another prior art package design used on a Japanese concentrated mouthrinse product differs from the prior art package used in Germany in that it employs a V-shaped well at the bottom of the dose cup for measuring the mouthrinse concentrate, and the water dilution line is marked by an inflection of the cup shape. The shape of the dose cup is generally rectangular with radiused corners, which is not ideal for instantaneous mixing of the concentrate with dilution liquid when the liquid is added to the cup. More importantly, this Japanese design requires the user to remove the outer dose cup and then unscrew a sealing cap before dispensing of the mouthrinse concentrate can be carried out. Thus the user must either handle three separate components, i.e., the dose cup, the sealing cap and the container, with only two hands or set one of the components down before proceeding to dispense concentrate from the container. This is awkward.
In addition to the foregoing prior art market place approaches which are used specifically for concentrated mouthrinses, there are a number of prior art patents which generally disclose other approaches to dispensing and measuring liquids from containers. However, the majority of these prior art patents do not address the specific needs of dispensing a concentrated liquid, such as a mouthrinse, to be diluted accurately, yet easily and quickly in conjunction with the problem of maintaining product integrity/stability between successive use cycles.
In this regard, U.S. Pat. No. 4,416,381 issued to Swartout on Nov. 22, 1983 discloses a bottle cap forming an integral measuring cup and bottle closure. The cup has graduations for measuring different amounts of liquid from the bottle. However, because the closure is used merely for measurement and not for dilution, there is no concentrate reservoir of smaller cross-section for accurately measuring a liquid concentrate to be diluted within the measuring cup, nor does the package include a limited cross-section spout to provide flow control, which is very important when measuring small quantities of concentrated liquid. What's more, most of the package embodiments disclosed by Swartout expose the measuring cup portion of the closure to the surrounding atmosphere before and after the package is placed in service, thereby permitting contamination of the measuring cup portion of the closure before and after the package is placed in service by the user.
U.S. Pat. No. 2,543,427 issued to Warne on Feb. 27, 1951 also discloses a combined closure cap/measuring cup. Like Swartout, the measuring cup of Warne is not used for dilution purposes. Furthermore, like most of the embodiments disclosed by Swartout, Warne places the measuring cup in an upright and exposed position when the closure is used to seal the bottle. Thus the measuring cup portion of the closure is exposed to contamination from the surrounding atmosphere and environment not only before the package is placed in service, but also between use cycles after the package has been placed in service by the user. This is highly undesirable for an ethical care product, such as a concentrated mouthrinse.